Dowel pin, stud, or the like



Feb. 27, 1934. I 5, sum; 1,948,889

DOV IEL PIN, STUD, OR THE LIKE Filed March 24, 1931 Patented Feb. 27, 1934 1,94s,ss9

DOWEL PIN, STUD, OR THE LIKE Ernst Simon, Berlin, Germany Application March 24, 1931, Serial No. 524.954

Germany April 15, 1930 4 Claims.

This invention refers to dowel pins, expansion plugs or sleeves of great resisting strength and adapted to be driven in railroad ties or sleepers for receiving fastening means. The expansion 5 plug or sleeve according to this invention is provided with ribs or collars distinguished from the state of the art by the fact that the surfaces of the ribs are differently inclined in accordance with the particular kind of stresses which they have to resist; In the dowels of the kind referred to, as heretofore constructed, these ribs or collars which are particularly intended to increase'the resistibility of the sleeves or plugs against strains in the longitudinal direction, have both of their sides either provided with inclined surfaces similar to ordinary screw threads, or the flanks of the ribs which are strained, when the dowel is subject to tensile stresses, present steep surfaces with relation to the body of the plug with a view of 2 facilitating the insertion and the forcing of the plug into the hole intended for its reception and with the additional purpose of imparting a particularly high degree of resistance against withdrawal of the expansion plug.

Now, in accordance with this invention the sleeve or expansion plug is provided with ribs or collars having steep flanks to resist the action of compressing stresses upon the sleeve or plug. Such pressures or compressing stresses will for in- 0 stance occur in the case of plugs made of hard wood, which are inserted into railroad ties composed of soft wood. Such plugs are adapted to absorb the forces to which the ties are submitted by the action of the rolling weights in a particularlyadvantageous manner and to deflect these forces away from the softer surface of the ties upon which they will ordinarily produce a considerable wearing-out action.

In case tension stresses and pressures are alternatingly acting upon the plug the invention provides for the arrangement of steep flanks on one part of the length of the plug, where the pressure and compressing strains are to be absorbed, while in another part of the surface of the plug the arrangement is such that those flanks of the ribs or collars intended for the absorption of the tensile stresses are steeply disposed with relation to the main body of the plug. Notwithstanding the steep arrangement of the plug flanks upon which the pressing stresses are to act, plugs of this kind, as has been found by practical tests, may be inserted with comparative facility, particularly in case the ribs or collars for the absorption of the pressure are disposed at the upper part of the plug. The portion of the wood which has been displaced by the inserting action will re-enter the spaces'between the ribs and will thereby securely retain the plug in position.

On the accompanying drawing two embodiments of the principles of the invention are shown 00 in side elevation and plan view respectively, Figs.

1 and 2 representing one form of exempliflcation, while Figs. 3 and 4 refer to another modified exemplification.

In the form of construction according to Figs. 1 66 and 2, reference character h denotes a tie or sleeper in section. The flanks a of'the annular ribs 0 surrounding the expansion plug or sleeve 12 are arranged at right angle with relation to the body part of the plug at that section thereof which 70 is acted upon by the pressing forces to which the plug is subjected, while the flanks d at that side of the ribs or collars c subjected to tensile stresses are inclined.

In the exempliflcation according to Figs. 3 and 4, however; the kind of ribs or collars just described is only provided on the upper half portion of the plug, while in the lower portion thereof the corresponding asymmetrically disposed ribs or collars are reversed. The steep flanks (n are so therefore disposed at that side which is exposed to the action of tensile stresses of the plug, while the inclined flanks (11 are arranged at that side which is exposed to pressure. Thus, the dowel of this kind will resist particularly well to both as pressing as well as tensile stresses.

The hole 1 in the plug tapers towards the inner end of the plug and is adapted to receive the rail spike and the slots 0 in the inner end of the plug facilitate the driving of the dowel into the tie hole. 00

It should be understood that the invention may find expression in other embodiments and may be modified in accordance with the principles laid down in the appended claims.

I claim:--

1. An expansion plug or sleeve for railroad ties adapted for receiving a spike, comprising a body portion, a series of annular conical collars around said body, said conical collars having a cross section with tapering sides converging towards the 10 head end of the expansion plug and with base sides being substantially perpendicular with relation to the axis of the expansion plug.

2. An expansion plug or sleeve for railroad ties adapted for receiving a spike, comprising a body portion, a series of annular conical collars around said body, said conical collars having a cross section with tapering sides converging towards the head end of the expansion plug and with base sides being substantially perpendicular with rela- 1m tion to the axis of the expansion plug, and an axial extension of said body, a second series of conical collars on said extension, said second series of collars facing in opposite direction to said first series of collars.

3. A dowelling for railroad ties comprising an expansion plug driven into the tie-holes and having a series of annular conical collars on its body, said conical'collars having an upper surface converging to the upper surface of the tie and having a lower surface substantially parallel with said upper surface of the tie.

4. A dowelling for railroad ties comprising an expansion plug driven into the tie-holes, one part of its length being provided with a first and a second series of annular conical collars around its body, said first series of conical collars situated tion of the plug, said second series of collars facing in opposite direction to said first series of collars.

ERNST SIMON. 

